Er, help me out, I’ve been staring at the picture, pen poised, for 20 minutes and I haven’t ringed a single difference

See that big air intake under the bumper? See how the ends point upwards instead of down? And see that that horizontal chrome bar running between the two foglights? What are you, blind? How could you possibly miss such fundamental styling changes?

Is that the sum total of three years' work for a team of crack designers?

Pretty much. They did change the front lamp lenses, making them clear, and tweaked the rears to incorporate the LEDs now found in other more recent BMWs. The kidney grille surround is now flush with the bumper and there’s something new about the sills that apparently makes the car look longer.

So what's going to persuade me to trade-in my perfectly good pre-facelift 5-series?

The new one does lots of clever things. Take the Lane Departure warning system that warns you that you’ve wandered over white lines by sending a vibration through the steering wheel. Or the ‘Stop and Go’ feature of the Active Cruise Control that, unlike most other active cruise systems, works right down to a stop and back up again all by itself. It won’t do a full emergency stop, but in your average stop-start trickling rush-hour jam, it promises to be a real help. We had a quick go in Lisbon traffic but not enough to find out how polished it really is. We’ll have to wait for another go back in the UK to find out. The electric gearstick is new (although we've seen it before on the X5), but it's not that clever. It works well enough - just like the old one in fact, but no better.

Is it as good to drive?

Better. All three six-cylinder petrol engines (2.5-litre 523i, 3.0 525i and 530i) get direct injection and the diesels come with a newer version of the common-rail injection system. Almost all now have more power. The 523i for example climbs 13bhp to 190bhp, and the 530i and 535d get 14bhp-apiece, taking them to 272bhp and 286bhp, respectively. The biggest impact though, is on fuel economy. Those new petrol engines are staggeringly efficient: the 530i gets to 62mph in 6.5sec and is limited to 155mph yet manages 37mpg, even mated to an auto box. That compares well with the old car’s 30.4mpg and isn’t miles behind the 530d’s 44.1mpg, meaning that at last you no longer need to justify choosing a really enjoyable big petrol Five over the diesel version that has been the default choice for so long. And if you opt for the optional Sports auto 'box available from summer (as opposed to the regular auto), you get quicker shift times and a set of paddles behind the wheel for the first time on a non-M 5-series. Shame they're the confusing push-pull sort rather than the M5's more satisfying and more logical one for up a gear, another for down layout.

Any downsides?

All that technology doesn’t come cheap. Prices are up between £745 and a massive, £1745 depending on model (and both the Lane Departure and Active Cruise are optional on most models). At least the lower CO2 emissions and better fuel consumption will help offset some or all of that cost for company car users.

Verdict

Don’t be fooled by the same-again styling: underneath the sheet metal the 5-series is a fundamentally better car. Cars like the 530i won’t refreeze the ice caps but they prove that technology exists to make cars more environmentally friendly - without losing their ability to entertain.